The present invention relates to a call waiting indicating method and system and, more particularly, to an originating subscriber-initiated call waiting indicating method and system, in which an originating subscriber can talk to a busy terminating subscriber in accordance with the will of the originating subscriber.
In a conventional telephone switching system, a so-called call waiting service is offered to a subscriber as a service for calling the subscriber even if his or her line is busy. This call waiting service is offered to only a subscriber to allow connection in a busy state. At the same time, when a call is made to a non-subscriber in a busy state, a busy tone is sent back to the originating subscriber, and connection to the terminating subscriber in a busy state is not performed.
In the conventional call waiting service, the connection is allowed in a busy state, depending on the subscription conditions of the terminating subscriber. For this reason, if the originating subscriber wants to urgently talk to a busy non-subscriber, this terminating call is not allowed. The originating subscriber must call this terminating subscriber again upon an ON-hook of the terminating subscriber.